Printer

ABSTRACT

A plurality of printing components each are attached to a movable transport means to extend along a line of print with respect to a recording means. A permanent magnet is attached to each of said components and an electromagnet is fixed in spaced relationship to said permanent magnets. The permanent magnets having their polarity varying alternately from component to component. The electromagnet is selectively excited with a given polarity to produce a deflection of one or more permanent magnets in the direction of the recording means to cause the print component to print thereon.

United States Patent [1 1 Ludin I I PRINTER [75] Inventor: Ludwig Ludin,Anglikon,

Switzerland [73] Assignee: Camille Bauer Messinstrumente AG,

Wohlen, Switzerland [22] Filed: Oct. 3, 1973 [21] Appl. No.: 403,329

[30] Foreign Application Priority Data Oct. 6, 1972 Germany 2249125 [52]US. Cl. l0l/93.l5; 101/93.29; 346/139 A;

346/141 [51] Int. Cl. B41J 9/04 [58] Field of Search 101/930, 93.15,93.29;

[56] References Cited UNITED STATES PATENTS 3,300,017 l/1967 Yazejian eta1. 197/1 R 3,318,429 5/1967 Burns et a1 147/1 R N In 1 S h S d 11]3,924,528 [451 Dec. 9, 1975 Kleinschmidt et a1. 101/93 C X 3,603,4429/1971 Ward 101/93 C X 3,698,529 10/1972 Cattaneo.... 101/93 C X3,742,846 7/1973 Knappe 101/93 C 3,780,650 12/1973 Meier l0l/93 CPrimary ExaminerEdgar S. Burr Assistant Examiner-Edward M. CovenABSTRACT with a given polarity to produce a deflection of one or morepermanent magnets in the direction of the recording means to cause theprint component to print thereon.

12 Claims, 2 Drawing Figures U.S. Patent Dec. 9 1975 Fig '1 US. PatentDec.91975 Sheet 2 of2 3,924,528

PRINTER BACKGROUND OF INVENTION or other sheet recording support means.Print hammers are spaced at a distance from the support to the otherside of the sheet support means, and an ink ribbon is arranged betweenthe sheet and the type. The print hammers are pivotable about an axisrunning parallel to the line of print and are actuated by tappets whichperform a translatory movement along their axis. The tappets are in turnactuated by a pivoting armature of an electro-magnet whose pivoting axisis arranged parallel to the axis of the print hammers. Several printhammers, tappets and electromagnets are provided. A disadvantage of thistype of device lies in the fact that the power transmission from theelectromagnets to the print hammers takes place through severalmechanical parts each of complicated design. At high printing speedthese parts are exposed to considerable acceleration and forces whichmake wear at the joints and connections unavoidable. The efficiency ofthe arrangement is relatively poor. Further, multiple directionalchanges occur in translating rotary movement to linear movement and backagain to rotary movement. On each such change in direction a portion ofthe force of the driving power of the electromagnet is lost. Because ofthis, the electromagnet has to be made relatively strong and large. Alarge control output is necessary to operate the electromagnet. As aresult, the response constant of the electromagnet is greatly increasedhaving a disadvantageous effect on the speed which can be attained forprinting. Another disadvantage lies in the fact that the rate ofresponse of the electromagnet is relatively slight since the armatureshave to be constantlymagnetized and demagnetized. Another drawbackresides in the fact that due to the large number of engaging andconnecting points between components a considerable degree of noise isproduced which results in a troublesome noise level for the operatorunless sufficiently dampened or insulated. Finally, this type ofapparatus requires complicated correction devices to compensate forchordal error. This error arises because a print is provided for severalprinting spaces or gaps. The necessary adjustment is made by slewing orangularly positioning the hammer along a circular path.

Printers are also known, for use in conjunction with measurementrecording devices which are in the form of curve-recording-dot printersby means of which electrical measurements are expressed as curve dots orother symbols. As the printing unit, these well known printers have achopper bar or a printing drum. Besides the curve dots, additionalsymbols, e.g. numbers allotted to a measuring point, can also beprinted. These well known printers nevertheless perform very complexmechanical movements which require a very complicated and accuratemanufacture of the individual parts- Furthermore, in the printingoperation considerable forces have to be transmitted, so that the use ofrelatively strong parts is needed. This presupposes the structure oflarge masses, whereby undesirable inertia is created leading on the onehand to considerable wear and on the other hand to a relatively slowprinting sequence. These well known printers are therefore only suitablefor recording slowly variable factors.

It is the object of the present invention to provide a graphic recordingdevice and printer therefor overcoming the numerous disadvantages anddifficulties found in the prior art devices.

It is a further object of the present invention to provide a printer ofthe type described in which a higher printing speed ispossible, withfewer moving parts and with considerably smaller masses to be moved.

These objects, other objects and the numerous advantages of the presentinvention will be apparent from the following disclosure.

SUMMARY OF THE INVENTION According to the present invention a graphicrecording device is provided in which a plurality of printing componentsare attached to a movable transport extending along the line of printingwith respect to a recording means. A permanent magnet is secured to eachcomponent and an electromagnet is fixed in spaced relation to thepermanent-magnet between the transport and the recording means. Thepermanent magnets have their polarity varying alternately from componentto component. The electromagnet is selectively excited with a givenpolarity to thereby produce a deflection of the permanent magnet and thecomponent. Preferably, the electromagnet comprises a pair of opposedpoles lying in the direction of the line of print, one of the polesbeing provided with an exciter winding which is connected to a controldevice which emits a direct current pulse of selected polarity inresponse to a given signal from the measuring device, or other source tobe graphically recorded.

Preferably, the print componentscomprise a type face attached at one endof a resilient, spring-like arm, which is secured at its other end tothe transport, the arm extending cantilevered therefrom in a directionnormal or perpendicular to the direction of movement of the transport.The transport may be in the form of a continuous belt and/or chainconveyor.

According to one form of the invention, several electromagnets areprovided whose air-gaps are arranged in parallel planes offset betweenthe transport and the recording device and correspondingly offsetpermanent magnets are allotted to each electromagnet on selected printcomponents. In this way the number of symbols that can be printed at anyone time can be increased.

The printing is recorded on a sheet of paper or the like which issupported on a roller or spaced roller transport device and is movablein a direction normal to the movement of the print component transport.By selectively moving each with respect to the other, in well known andconventional manner, the print may be made on the recording sheet atselected graphical coordinates.

In well-known printers the ink support or ribbon is provided immediatelyat the point of printing. This is often undesirable, because this zoneis not readily accessible and the ink support has to be occasionallychanged or re-inked. Moreover, when the recording sheet support isinserted the latter may come to rest on the inking support, and therebybecome undesirably inked or soiled. In a form of carrying outthe presentinvention, therefore, at least one further electromagnet, arranged awayfrom the printing point, is provided for inking the printing components.The inking vehicle is therefore also arranged away from the printingpoint,

and the printing component is inked and then printed. To produce themovement of the printing component towards the inking support orvehicle, the further electro-magnet is provided.

In the preferred form of utilizing the invention, the printer is in theform of a recording instrument for the dot or symbol recording of one ormore variable measurement factors. Each measuring factor is representedby a curve composed of dots and the individual dots can have shapesdeviating from each other, for instance in the form of a dot, cross orcircle.

Full details of the present invention are given in the followingdescription of several practical embodiments thereof and in theaccompanying drawings.

BRIEF DESCRIPTION OF DRAWING DESCRIPTION oF TIIE'INVENTION In theembodiment of theinvention depicted in FIG. l, the printer comprisesatransport 1 shown in the form of a continuous belt conveyor. Thetransport may be a belt'or a chain, entrained over suitable means, notdepicted here-since the same are well known to those in this art. Thetransport is adapted to move linearly or be reciprocated along thedirection indicated by the arrow X. Extending cantilevered from thetransport 1 are a plurality of supporting arms 8 (only twoare shown).The arms 8 are resilient and extend perpendicular to the line ofmovement of the transport. The arms may be secured to the transport byany suitable known means depending of course on whether the transport isa belt, chain or is in another. form. A permanent magnet 2 is secured oneach arm 8. The arm 8 may extend through the magnet and be retainedeither by suitable screw means, adhesive welding,'etc. The permanentmagnets 2 are bar magnets and are arranged so that their polarityalternates from one to the other, adjacentmagnets having opposingpolarity. The polarity indicated in the drawing are illustrativeand notnecessarily restrictive.

' An electromagnet having opposing pole cores 3a and 3b, aligned withthe permanent magnets 2 is arranged adjacent the transport 1. The cores3a and 3b are spaced so that the magnets 2 pass freely between them. Onecore of the electromagnet is provided with an exciter winding 4 which onreceipt of a current pulse excites the associate core with selectedpolarity. The pole core may be made of soft iron or the like. Theexciter winding 4 is connected to a control device 4a which may includepulse generator, relay or similar device by which a direct current pulseis produced in response to an external stimuli. Such devices are notshown herein as they are well known in the art. Any suitable controldevice may be used. I

The magnets 2 are preferably bar magnets having theiraxis of polaritynormal to the, arm 8 and lying in the vertical plane formed between thepole cores 3a and 3b. The use of a permanent magnet creates adynamicsystem in which the active component, i.e. magnets 2, is continuouslymagnetized and deflected merely on modification of the flux field.

A printing component 5 is secured to the free end of each of the arms 8.The printing component carries the character, or type to be imprinted;for instancea dot or other symbol such as a cross, zero or standardletter or number type. The print component 5 is arranged to one side ofan ink ribbon 6 which lies above a record sheet 7 such as an endlesspaper strip or the like. The sheet 7 is entrained over a roller whichacts as a platen for the print component 5.* The sheet is driven to movein a direction indicated by the arow Y, normally i.e. perpendicularly,with respect to the line of travel of the transport 1.

The supporting arms 8 are preferably made of flexible spring material,such as leaf or bar springs. The attachment of the arms Q to thetransport 1 also preferably is provided with a degree of flexibility orelasticity, depending of course on the nature of the transport. The arms8, however, must extend outwardly sufficiently rigidly so that theprinting component remains in a sub stantially fixed position withrespect to the transport. Therefore, if the attachment to the transportis elastic, the arm must be less so and vice versa.

As will be obvious, the print components 5 move in a straight line ofprint, parallel to the direction of travel X of the transport 1, whilethe record sheet 7 moves in a direction Y perpendicular to it. Thus onproper control or indexing of the transport and the record sheet theprint component can be made to print a symbol on the sheet at a givengraphical horizontal and vertical set of coordinates, as indicated bythe pattern of dots, seen on the sheet 7. Thus printing is accomplishedby selectively exciting the winding 4 with a given polarity so as torepel the permanent magnet of the selected print component and deflectit downwardly against the ribbon 6, and sheet 7.

The entire arrangement is preferably of such dimensions, that there arealways two permanent magnets 2 of opposite polarity in the air gap ofthe electromagnet at the same time. By an appropriate choice of thepolar ity of a control signal passed'to the exciter winding 4', one ofthe permanent magnets 2 andtherefore one of the printing components 5for the printing operation can be deflected downwardly, while the otheris deflected upwardly. This leads in practice to doubling of thepressure frequency, in comparison to those devices in which there isonly a single permanent magnet in the zone of the electromagnet. It isof course also possible to arrange the system in such a way that thereis only one permanent magnet at a time inthe air gap of theelectromagnet.

The permanent magnets 2 have relatively small dimensions when a materialof highcoercivity or permeability is used, as for instance samariumoxide. As a result the mass of the supporting arms 8 and also that ofthe printing components 5 can be relatively slight.

.Thus, the printer described has extremely low mass inertia, providing afurther increase in the printing frequency and speed in relation to wellknown printers of thisvtype is furnished.

With the use of the printer as a type printer, i.e. to provideanon-coded or coded message, the printing ,type or characters can bearranged in a determined se- With the use of the printer as a graphicalrecording device, in which the outline of the curve of one or moremeasuring factors is to be recorded as a function of time, the printingcomponents are provided with simple symbols, for instance dots,triangles, circles etc. In this case also the transport device 1 maytake any form, for instance that of a revolving belt. In the case of thesimultaneous determination of several measuring factors, a printingsymbol is allotted to each measuring factor, and in this example, bymeansof a suitable control device that isnotshown here, coordinationbetween the printing symbols and the measuring factor and the correctprinting moment are fixed.

It is finally possible to combine both type printers and recordingprinters with one another, so that for instance on the edge of arecording strip that is moved on as a function of time, the clock timeand/or the number of a measurement point and/or other alphanumericalcharacters can be expressed, while at the same time the curve outline ofthe measuring factors is recorded in the form of dots. (See FIG. 2):

The transport device, in particular when it is in the form of a conveyorbelt, can itself contain coding, for instance punched coding after themanner of the well known punched strip, with the help of which therequired printing components can be selected for printing, by a signalgenerator, computer or the like.

It is also possible to arrange the inking ribbon 6 at another point ofthe printer, especially in the zone out of reach of the record sheet 7.That is, an inker may be arranged along the path of travel of the print.Components and an auxiliary electromagnet are provided by which theprinting components are first deflected on the inker, and thus preparedfor the actual printing operation. This measure dispenses with the oftenunpleas ant manipulation of an inking ribbon, in the actual printingzone. The separate inker may be a ribbon, well or other device.

The special advantage of the printer according to the invention residesin the fact that it makes it possible to attain a very high printingspeed. This is on the one I hand, due to the fact that the number ofmoving parts and the size of the masses moved are very small. Moreover,no change in power direction is needed to move the magnets. The drivingpower can also be kept low since losses associated with changes of thedirection of the force are avoided. Finally, through the electrodynamicdrive system that is used according to the invention, in contrast to theelectromagnetic driving systems heretofore known an additional increasein the operating speed is possible. The armatures do not have to beconstantly magnetized and demagnetized. As the excitation output can bereduced in relation to the wellknown printer due to the reduced energyrequirement, not only is a reduction in the pulse output possible; it isalso possible to obtain a quicker printing sequence, because the polesof the electromagnets to be magnetized can be reduced in volume. A veryspecial advantage also resides in the fact that the printer according tothe invention operates very noiselessly. It does not there'- forerequire sound proofing, nor will it annoy persons present in the sameroom.

In FIG. 2 a further practical example of a printer is described, inwhich the printing components are arranged in considerable density alongthe transport device 23. According to the principle of the examplepreviously described there may only be a single, permanent magnet with adetermined polar direction, in the air-gap of the electro-magnet.According to the practical example of FIG. 2, several electromagnets 21and 22 are provided, (two are shown) whose air gaps are arranged onplanes A and B running in the direction of the transport device 23 andthe recording track 24. At the same time, the poles of theelectromagnets extend thewidth of sheet 25 either wholly or partially.If the width of sheetis entirely covered, a-printing operation can becarried out at any point of the strip of paper. If there is only partialoverlap, printing is of course only possible for the zone covered.

The permanent magnets attached to the supporting arms are thereforecoordinated in pairs to the different electromagnets, according to thearrangement of FIG. 2. The pair of permanent magnets 26a is thereforearrangedat the plane A corresponding to the first electromagnet whilethe pair of permanent magnets 26b is arranged on the plane B of thesecond electromagnet. In thisway the result may be obtained, accordingto FIG. 2 where printing components 27a, which are allotted to the pairof permanent magnets 26a and the electromagnet 21' covering the fullwidth of the paper, are arranged on plane A and print throughout thewidth of the sheet typecharacters, e.g. figures, while with the sametransport device other printing components 27b, which are allotted tothe pair of permanent magnets 26b and the electromagnet 22 on the planeB, record in the form of dots the curve of the measurements. It is ofcourse also possible to provide other such groups of magnets to printany indicia desired. It is not necessary here for the poles of all theelectromagnets to extend throughout the length of the line of writingalthough the printing type to be printed and actuated by thiselectromagnet do not have to be printed throughout the whole width ofthe recording support.

In general, the arrangement shown in FlG. 2 comprises componentsdesigned and combined in the manner described in connection with FIG. 1.Several other changes, modifications and embodiments will be obvious tothose skilled in this art. The description therefore is to be taken asillustrative only and not limiting of the scope of the invention.

What is claimed is:

l. A printer comprising a plurality of deflectable printing componentsand a recording means, each of said components being attached to amovable transport means adapted to sequentially carry said printingcomponents in a path extending along a line with respect to saidrecording means, a permanent magnet attached to each of said componentsto move conjointly therewith and an electromagnet fixed in spacedrelationship to the line of movement of said permanent magnets, saidpermanent magnets being adjacent said recording means, said permanentmagnets having their polarity varying alternately from component tocomponent, and means for selectively exciting said electromagnet with agiven polarity to produce a force field on at least one permanent magnetto thereby cause deflection of selected printing components in thedirection of said recording means to cause said print component to printthereon.

2. The printer according to claim 1 wherein said electromagnet comprisesa pair of spaced poles providing an air gap therebetween in which saidpermanent magnet may move, said poles having a length such that the gapextends over the permanent magnet of at least one printing component,and an exciter winding arranged about at least one of said poles.

magnets of each of the associated sets are coordinated 3. The printeraccording to claim 2 including means for producing a direct currentpulse of selected polarity in said exciter winding.

4. The printer according to claim 2 wherein said printing components arespaced along said transport means with respect to each other a distancewhereby the permanent magents of at least two of said printingcomponents pass through said air gap between the poles of saidelectromagnet at the same time.

5. The printer according to claim 1 wherein each of said printingcomponents comprise an elongated resilient arm having printing means atone end and being thereto.

8. The printer according to claim 1 wherein said transport meanscomprises an endless conveyor and said printing components arecirculated past said recording means. I

'9. The printer according to claim 1 including an ink carrier arrangedbetween said printing components and the recording means to transfer inkto said recording means on deflection of said printing components.

10. The printer in accordance with claim 1 wherein each of said printingcomponents is provided with a predetermined symbol.

v 11. The printer according to claim ,10 wherein said recording meanscomprises an elongated sheet movable in a direction normal to themovement of said transport means and means for moving said sheet.

' 12. The printer according to claim 1 including an ink carrier spacedfrom said recording means alongthe path of travel of said printingcomponents and one of said electromagnet being operable on excitation.to deflect said printing components toward said ink carrier to be inkedthereby. l

1. A printer comprising a plurality of deflectable printing componentsand a recording means, each of said components being attached to amovable transport means adapted to sequentially carry said printingcomponents in a path extending along a line with respect to saidrecording means, a permanent magnet attached to each of said componentsto move conjointly therewith and an electromagnet fixed in spacedrelationship to the line of movement of said permanent magnets, saidpermanent magnets being adjacent said recording means, said permanentmagnets having their polarity varying alternately from component tocomponent, and means for selectively exciting said electromagnet with agiven polarity to produce a force field on at least one permanent magnetto thereby cause deflection of selected printing components in thedirection of said recording means to cause said print component to printthereon.
 2. The printer according to claim 1 wherein said electromagnetcomprises a pair of spaced poles providing an air gap therebetween inwhich said permanent magnet may move, said poles having a length suchthat the gap extends over the permanent magnet of at least one printingcomponent, and an exciter winding arranged about at least one of saidpoles.
 3. The printer according to claim 2 including means for producinga direct current pulse of selected polarity in said exciter winding. 4.The printer according to claim 2 wherein said printing components arespaced along said transport means with respect to each other a distancewhereby the permanent magents of at least two of said printingcomponents pass through said air gap between the poles of saidelectromagnet at the same time.
 5. The printer according to claim 1wherein each of said printing components comprise an elongated resilientarm having printing means at one end and being attached at the other endto said transport means said magnets being arranged between the endsthereof.
 6. The printer according to claim 5 wherein the permanentmagnets of said printing components are offset in selected sets betweenthe ends of said arm, and an electromagnet is provided for each of saidsets of permanent magnets.
 7. The printer according to claim 6 whereinsaid electromagnets are arranged in parallel planes between saidtransport means and said recording means and the magnets of each of theassociated sets are coordinated thereto.
 8. The printer according toclaim 1 wherein said transport means comprises an endless conveyor andsaid printing components are circulated past said recording means. 9.The printer according to claim 1 including an ink carrier arrangedbetween said printing components and the recording means to transfer inkto said recording means on deflection of said printing components. 10.The printer in accordance with claim 1 wherein each of said printingcomponents is provided with a predeterminEd symbol.
 11. The printeraccording to claim 10 wherein said recording means comprises anelongated sheet movable in a direction normal to the movement of saidtransport means and means for moving said sheet.
 12. The printeraccording to claim 1 including an ink carrier spaced from said recordingmeans along the path of travel of said printing components and one ofsaid electromagnet being operable on excitation to deflect said printingcomponents toward said ink carrier to be inked thereby.